Your sex life used to sizzle, but lately the heat between the sheets has turned icy. The two of you may be suffering from a case of lopsided libidos. Find out how to get back in sync sexually. Plus, rate your sex drive with our quiz…

Douglas, a 30-something physician in central Florida, remembers a time in the not-so-distant past when he had rock ‘n’ roll sex with his wife.

Before they married and before their daughter was born, sex was not only frequent but inventive.

But about three years into their relationship, he noticed a marked change. Things his wife once enjoyed started dwindling and eventually were off the menu completely.

“It’s not just that she says ‘no’” he says. “It’s that she feels some of the things I suggest – things she used to do – are wrong.”

Nowadays, sex feels so much like a grudging obligation that he can’t help but wonder what happened to the lively gal he dated, the one who pulled up her top and flashed him while dancing in a nightclub.

“It feels like a bait and switch,” he says.

Douglas (whose name was changed to protect his privacy) is hardly alone in his frustration. Desire differences – or “lopsided libidos,” as Canadian sexpert Josey Vogels calls them – are among the most common problems that crop up in relationships.

Indeed, about 90% of couples find they’re out of sync sexually at some point in their relationships.

And though the cliché is that guys always push for more and women resist, the reverse happens too.

“Guys aren’t going to brag to their buddies that they’re not that interested in sex, so we tend to hear about that dynamic a lot less,” says Vogels, author of Bedside Manners: Sex Etiquette Made Easy (HarperCollins Canada).

Why do couples go from We’ve gotta have it now to Not tonight, dear?

The factors that can diminish desire is long and varied.

Everything from job stress and money woes to depression and certain medications can cause a decline in hormone levels.

Life changes – having a baby, moving or losing a loved one – can put a damper on your activities.

Or your lackluster libido might be due to performance anxiety, poor body image or annoyance with your partner.

But in many cases, experts say, mismatched sex drives are simply normal in a long-term relationship.

“When people are together at the beginning, there’s a lot of brain chemistry happening that helps a couple feel excited about each other and makes them more interested in sex,” explains Stephanie Buehler, a certified sex therapist and director of The Buehler Institute in Irvine, Calif., which helps couples restore intimacy through sex therapy.

"Then the chemicals wear off, life starts to interfere and your priorities change to making sure the household is running.”

Still, that doesn’t mean it should be a permanent frustration in your relationship.

Here, sex experts offer five strategies for striking a balance in the bedroom:

1. Talk about ItLike many couples, you may not be jumping at the chance to discuss problems in your sex life.

But when you don’t acknowledge an imbalance, getting into bed each night evolves into a tense, unspoken tug-of-war in which one of you feels perpetually pressured and the other one feels denied.

“There’s this primitive communication,” Vogels says. “He reaches out, she shrugs him off and you both roll over and wonder whatever happened to all that great sex you used to have.”

2. Help Yourself Get into the Mood“Take responsibility for feeling sexual,” Vogels says. “We think our partner doesn’t understand how tired we are or they’re not doing the right thing. But we need to be honest with ourselves about what’s stopping us”

If you’re the one with the lower sex drive, think about how to rev yourself up. It could be as simple as having your husband get the kids ready for bed, so you can decompress and mentally switch gears from mom to sex kitten.

Maybe you need a prolonged back rub with scented oils to help you reconnect with your body and sexuality.

Or mixing up your routine might be all you need to shift your sex drive into gear: Try getting frisky on the couch before retiring to the bedroom.

“The person with the high drive has to see this as an opportunity for seduction and figure out how to invite the person with the low drive to have more sexual experiences,” Buehler says. And the person with the low drive has to figure out what will get them into the mood more often.

3. Broaden Your Definition of SexDon’t fret that you’re not having intercourse. Instead, expand your concept of sex and find other ways to enjoy one another’s bodies. That could mean anything from oral sex to intimate touching to drawing inspiration from a sexy flick.

Toys can also help partners connect in the bedroom. One client of certified sex therapist Michele Sugg had a lower sex drive than his wife. So he was happy to use a vibrator on her.

“His wife could have orgasms and feel close to him, but he didn’t have the performance pressure,” Sugg says.

As long as you both feel good, it doesn’t matter what you’re doing.

4. Find a CompromiseUltimately, if your drive differences are more than a temporary blip, there must be some give and take.

“Approach it as a problem to be solved,” Buehler says.

Consider what you can do as a couple to help you both be happy and satisfied.

Perhaps if one of you wants sex daily while the other is content with weekly, committing to twice a week is a reasonable compromise.

Sometimes it’s all about scratching that itch. But at times wanting more sex may indicate a longing for a closer emotional connection, Sugg says. This can be achieved with more cuddling, giving each other massages or just talking.

5. Put Sex on Your To-Do ListScheduling an appointment for lovemaking – and not begging off – can certainly help.

“We all say we don’t have time for sex, but we have time to watch really bad reality TV shows all night,” Vogels says. “Putting sex on your to-do list doesn’t sound very sexy and spontaneous when you want it to just happen naturally, but you do need to make a conscious decision to put it on the table.”

Think of it as strength training for your sex drive – the more you use it, the stronger it’ll be.

“You go to the gym to stay in shape; it takes effort to keep your libido in shape too.”

Rate Your Sex DriveIs your sex drive running on fumes or is it revved up to go the distance? Find out where you rate on the sex-o-meter with this libido quiz and what you can do if you're running low on steam.

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